HeaderCssClass - Name of the CSS class to use for the headers. This can be either applied to the Accordion as a default for all AccordionPanes, or an individual AccordionPane.

HeaderSelectedCssClass - Name of the CSS class to use for the selected header. This can be either applied to the Accordion as a default for all AccordionPanes, or an individual AccordionPane.

ContentCssClass - Name of the CSS class to use for the content. This can be either applied to the Accordion as a default for all AccordionPanes, or an individual AccordionPane.

FadeTransitions - True to use the fading transition effect, false for standard transitions.

TransitionDuration - Number of milliseconds to animate the transitions

FramesPerSecond - Number of frames per second used in the transition animations

AutoSize - Restrict the growth of the Accordion. The values of the AutoSize enumeration are described above.

RequireOpenedPane - Prevent closing the currently opened pane when its header is clicked (which ensures one pane is always open). The default value is true.

SuppressHeaderPostbacks - Prevent the client-side click handlers of elements inside a header from firing (this is especially useful when you want to include hyperlinks in your headers for accessibility)

Panes - Collection of AccordionPane controls

HeaderTemplate - The Header template contains the markup that should be used for an pane's header when databinding

ContentTemplate - The Content template contains the markup that should be used for a pane's content when databinding